1. a mixture of salt and iron filings has a mass of 4.5g. a student determined that the iron
filings had a mass of 3.0g during a separation lab. what is the percent composition of
iron in the mixture?

The answer to your question is: 66.7 % of Iron filings

Explanation:

Data

Mixture salt - iron filigs = 4.5 g

Iron filings mass = 3.0 g

Formula

Percent composition = (mass of solute/mass of solvent) x 100

Percent composition = (3.0 / 4.5 g) x 100

Percent composition = 66.7%